This RNA binding domain is found at the C-terminus of a number of DEAD helicase proteins [1]. It is sufficient to confer specificity for hairpin 92 of 23S rRNA, which is part of the ribosomal A-site. However, several members of this family lack specificity for 23S rRNA. These can proteins can generally be distinguished by a basic region that extends beyond this domain [Karl Kossen, unpublished data].

1: Cloning and biochemical characterization of Bacillus subtilis YxiN, a DEAD protein specifically activated by 23S rRNA: delineation of a novel sub-family of bacterial DEAD proteins. Kossen K, Uhlenbeck OC; Nucleic Acids Res 1999;27:3811-3820. PMID:10481020

2: The carboxy-terminal domain of the DExDH protein YxiN is sufficient to confer specificity for 23S rRNA. Kossen K, Karginov FV, Uhlenbeck OC; J Mol Biol 2002;324:625-636. PMID:12460566